Maintenance won't make much difference in my knowledge as the de nitrifying bacteria live in the air pockets in the live rock and won't live in filters as they can only live in air as a result the nitrate is built by filter but there is no way to turn in back into harmless nitrogen. Not that nitrate is harmful to fish in small doses but only way to remove is to water change so plenty need to be done

Woody, I think you missed it a bit on aerobic or nitrifing bacteria. Aeorobic means oxygen rich WATER. The bacteria that breakdown ammonia and nitrite require oxygen in the water, not bubbles of air or pockets. The denitrifying bacteria, or anaerobic bacteria require oxygen free water. That occurs in the deeper parts of the rock structure that water can penetrate but does not readily replenish its oxygen and becomes anaerobic. That is where nitrate is broken down into nitrogen.

That being said, you are correct in that denitrifying bacteria cannot live in the filter membranes as the water's oxygen is constantly replaced.

I guess the point is that people that use Canister filters are just making more work for themselves?

I clean mine out every two to three weeks. That's when I do a BIG tank cleaning and it takes me an hour to do everything. The weeks in between I just take 10 gallons out of my 55 and replace it with fresh saltwater.

So I am correct in saying that the filters are fine so long as you clean them and maintain them. There is really no big benefit in having a Canister Filter or a Wet-Dry Filter over a sump tank correct? It just keeps the water clean and the water clear like they are suppose to and that's it!

What would a Sump tank advantage be over the filters? Besides less work!

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Fish Sticks, the best thing you can do with your dead fish.

Yes deep sand bed will de nitrify, and yes canister filters are ok of well maintained. The sump will house all of your equipment and make the display tank look better the skimmer will do a better job of filtering because it will pick organisms up that filter pads etc would not be able to. Sumps are great breeding grounds for pods for your tank and will also increase yOu water volume which is useful